Terminal mounting for resistances



April 9, 1935. QGG 1,997,198

TERMINAL MOUNTING FOR RESISTANCES Filed Jan. 31, 1931 INVENTOR R. A. 066

ATTORNEY retested A r, 9, i935 I 1,997,198

- UNITED. STATES" PATENT OFFICE TERMINAL MOUNTING FOB RESISTANCE Robert A. On, Towaco; N.- 3., assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application January 31 1931. Serial No. 512,513

3 Claims- (01. 113-324) g This invention relates to resistance elements the ends of the resistance wire element and from and the like and more particularly to a core the insulating base member be reduced to a member for supporting a resistance winding havminimum. ing terminal members securely fastened within a The insulating base members in some instances 6 portion of the core membe are made of ceramic material, such as porcelain I An object or this invention is to provide in reor Isolantite which in its finished or fired state sistance elements-and the like, a core member or is not adaptable for h Seeurenee Of terml ls insulating material having secured th ein a, et thereto by means ofscrews or rivets. of terminals which cannot become loose or sepa- In the Present invention terminal m mb for 10 rated from the core member. a resistance winding are secured in ,an enlarged 1o A feature of this invention resides in a block d p i n f an i sulatin bas m m r with-- portion integral ithth r d in h h tout bolts or rivets and are prevented from being able slots are provided to receive innerend poraccidentally dislodged therefrom and severed tions of terminal members. Another feature in from t ends of the resistance i d g y reason this invention resides in the employment of terof the Particular cooperating means Provided in 15 minal members having a. configuration conformthe base member and m ls as. well as by a ing t particmar form of slots n the block .suitable cement applied to the base member and portion of the core and which are cemented into termlmllsa the slots to prevent loosening bi! the terminal Referring to the drawing, 1 s a base m mbe members or separation iromthe core. Other feaof insulating material having a comparatively 20 tures residing in the provision or a tud member long cylindrical portion 2, an enlarged end 3, an in the block portion of the core to secure the ar ed block end portion 4 and Shoulder P rsistance it t a Suitable support and t tion 5 between the cylindrical portion 2 .and the vision of a soluble washer between an end of the enlarged block end Pertlen This base member 1 wire winding and a flange of t core and which I may be of ceramic material such as porcelain or 25 becomes a. homogeneous part of the protective Isolantite in feet y resistance material telmd serving on the winding aredisclosed in this s eciadaptable su ab y suppo tin a wire windin flcation. .In the enlarged block end portion 4 are slots In the drawing, 6-6 to receive terminal members 1-1. The side Fig. 1 is a view in perspective of a resistance Walls 8 forming a h s t 6 nve toward the 30 unit having an insulating ba e member t an open side 9 and overhang the base In. The slots enlarged end portion in which are secured a pair p bly, ar also tapered longitudinally of terminals; so that the width of the slot at the outer end I lis Fig.2 is a view in perspective of an insulating slightly less than the width of the slot at the inbase member and the terminal members separatd l 35 ed therefrom; The terminals 1 are preferably sheet metal. Fig. 3 is an end elevation of the enlarged end t mpings and have an nlarg d end 3 and a portion of the insulating base member; comparatively long narrow portion 14. The en- Fig. his a top view of the insulating base memlarged nd preferably are tap r to n rm 40 her and the enclosed portion of a terminal; substantially, with the longitudinal taper c t the 40 Fig. 5is atop view of Fig. 1 with portions broken slot 6 in the enlarged block end portion 4 of the away to disclosevarious portions of the resistance insulating base member I so that when the termi- 'winding and the insulating serving and a washer nal I is resting in the slot 6 longitudinal withinterposed between one end of the winding and drawal of the terminal I from the slot 6 in one a shoulder of the insulating base member; and direction is prevented. The enlarged end por- 5 Fig. 6 is a view in perspective of a modification tions 13 ofthe terminal are apertured at l5 tor a of the terminal shown in Fig. 2. purpose as will be later explained and the inner In resistance units of the type in which a reends l6 of the terminal I are reduced as shown at sistance wireelement is supported on a suitable l1 and provided with angularly disposed lugs l8 Q5 insulating base member and terminals are proto which the ends of a. resistance winding may be 'vided for extending the ends of the resistance ele- V attached. The width of the enlarged end portion ment to wires leading to other pieces of apparal3 of the terminal I at its inner end I6 is slightly tus, itis desirable that the terminals be so supless than the width of the base "I of the larger 'ported on the insulating base member that the or inner end 12 of the slot 6 so that when the r possibility of severence of the terminals from terminal 'I is Placed in the Slot 5 Sumeient Space 56 is provided between the edge portions of the enengagement with the larged end I3 of the terminal and the walls 8 of the slot 6 to allow the passage of cementitious material between the edge portions of theterminal and the walls of the slot. i

The depth of the slot 6 in the enlarged block end portion 4-is over twice the thickness of the terminal I as shown in Fig. 2 so that when the enlarged end slot 6 and rests on the base II] the walls 88 which converge toward the open side 9 overhang the enlarged end I3 of the terminal. I

The terminals are secured in the enlarged block end portion 4 of the base member I as shown in Fig. 1 by cement I9, which is applied over the enlarged end I3 of the terminal and fills the slot 6. When the cement is applied over the enlarged end I3 of the terminal and the slot 6 is filled with this cement, some of the cement is forced downward through the aperture I 5 in the terminal and into engagement with the base I 0. The width of the enlarged end I3 of the terminal being slightly less than the width of the base ID of the slot, some of the cement pressed into' the slot also passes around the edges of the terminal and into side walls 8 and the base I0. cemented into the enlarged the insulating base member With the terminal block end portion4 of I as shown in Fig. 1, in and some of the cement forced through the aperture I5 and around the outer edges of the terminal and into engagement with the walls 88 and the base I0, it is quite obvious that the terminal is securely fastened to the insulating base member I and cannot he accidentally dislodged from the insulating base member.

When the cement hardens it cannot fall out of the slot 6 because of the overhanging walls88. The pillar of cement which passes through the aperture I5 and into engagement with the base I0 prevents longitudinal withdrawal of the terminal from the slot in either an inward or outward'direction relative to the insulating base member I. Longitudinal withdrawal of the terminal from the insulating base member I in an outward direction is also prevented by the tapering of the slot and the converging of the side walls 8-8 toward the outer end of the enlarged block end portion 4.

On the cylindrical portion 2 of the insulating base member I is a winding of wire 20 as shown in Fig. 5 which is wound between the enlarged end 3 and the shoulder 5. The ends of this winding 20 are attached to the angularly disposed lugs I8 of the terminals 1. Over the winding 20 is applied a serving of rayon silk thread 2| and over this silk thread serving is applied a coating of cellulose acetate 22 which partially dissolves and forming an impervious protective coating over the winding.

Between the inner ends of the windings 20 and 2| and the shoulder 5 of the insulating base member I is a cellulose acetate washer 23 which is on the cylindrical portion 2 of the insulating base member I before the windings 20 and 2| er 23 is partially dissolved when the cellulose acetate coating 22 is applied, and unites with the I3 of the terminal is placed in the and the slot 6 entirely filled are formed. This cellulose acetate wash 9 cellulose acetate coating 22 and prevents the en-' trance of moisture between the inner ends of the windings and the shoulder 5.

Instead of using the tapered terminals shown in Fig. 2 with an enlarged tapered portion I3, terminals of the type shown in Fig. 6 may be employed. In this modification the enlarged end portion I3 is rectangular instead of being tapered and the width of the portion I3 is slightly less than the width of the base III of the slot 6'. When terminals of this type are used they are cemented into the enlarged block end portion 4 of the insulating base member I in the same manner as described for the terminals shown in Fig. 2.

Resistance units and the like of the type above described are often supported on a suitable frame or panel with the spoolportion of the unit extending from one face of the support and the terminals extending through the support and outward from the opposite side. To mount the nit on such a support a stud 24 is provided. One end of the stud 24 is embedded or threaded into the enlarged block end portion 4 of the insulating base member I. The outer end of the stud extends longitudinally of the base member I and is adapted to pass through an aperture in the supporting frame or panel and serve in cooperation with a suitable nut 25 as a means for se-- curing the unit to the support.

has been assumed to be of ceramic material such the terminals are secured to the core member as being a suitable porcelainous cement. The core member may, however, be made of any suitable insulating material and the cement for securing the terminals in thecore member may be any suitable cement for the purpose required, without departing from the spirit of this invention.

The invention disclosed is adaptable to units of inthe core member not well be secured is such that terminals may thereto by bolts or rivets or the type described in which the material used like fastening means and is only limited to the.

extent set forth in the following claims.

What is claimed is: v c 1. A support comprising. a core of ceramic material having a terminal block on one end, said bloclc having spaced walls forming undercut slots, electrical fterminal members fastened in said slots, and fastening means in saidslots for said electrical terminal members.

2. A support comprising a core of ceramic material having a terminal block on one end, said block having spaced walls forming undercut tapered slots, electrical terminal members tapered to conform to said slots, and fastening means in said slots for said electrical terminal members.

3. A support comprising a core and an oblong terminal block, on one end of the core, molded in one piece from ceramic material, said block having spaced walls forming a pair of undercut slots, flat electrical terminal members cemented in the bases of said slots, said flat electrical terminal members having their'inner ends projecting inwardly of the core andbeyond the inner nd of the block and having lugs projecting at right angles to the plane of the terminal members.

ROBERT A. OGG. 

